Grilled Salmon Fillets with Creamy Horseradish Sauce

Name: Grilled Salmon Fillets with Creamy Horseradish Sauce
Ingredients: 3/4 cup sour cream; 1/4 cup mayonnaise; 2 tablespoons prepared white horseradish; 2 tablespoons chopped fresh basil; 1 tablespoon fresh lemon juice; 1 teaspoon soy sauce; Nonstick vegetable oil spray; 3 tablespoons vegetable oil; 1 tablespoon prepared white horseradish; 1 tablespoon soy sauce; 1 small garlic clove, minced; 1/2 teaspoon salt; 1/4 teaspoon coarsely ground black pepper; 6 1-inch-thick salmon fillets (each about 6 ounces)